Update 1.5 was released to ensure that all players had a stable experience while navigating the Kalos region. While earlier patches (like 1.1 and 1.2) focused on game-breaking bugs, version 1.5 serves as a "catch-all" update that includes:

Pokémon X heavily utilizes the bottom touch screen for features like the Player Search System (PSS), Pokémon Amie, and Super Training. For the best layout on a single PC monitor, set the screen layout to or Side-by-Side inside the emulator's view settings. Map the touch screen cursor to your mouse or the right analog stick of your controller for seamless navigation. Legal and Safe Sourcing Reminder

Have you tried the Pokémon X 1.5 decrypted extra quality patch? Share your performance results in the comments below. And don’t forget to back up your save before installing any CIA updates.

Resolved menu image issues for Vivillon and Poké Ball animations during battle. Version Compatibility

However, the phrase in your keyword likely refers to Update version 1.5 (the numeral "1.5" being misread as "15"), or more excitingly – a fan-driven "15th custom update" that includes Quality of Life (QoL) improvements, 60 FPS patches, and anti-anti-piracy bypasses.